Establishing a specific diagnosis depends on a good history and physical examination. That said, the description you give sounds like a condition called seborrheic dermatitis, which is characterized by sometimes pink, dry, flaky skin that can involve the areas you mention and can also affect the eyebrows, scalp and ears as well. Effective treatments can include a topical antifungal cream such a ketoconazole and possibly a mild hydrocortisone cream if there is a lot of inflammation. Another diagnostic consideration is a condition called perioral dermatitits, which is a sort of hybrid between acne and seborrheic dermatitis. Seborrheic dermatitis and perioral dermatitis can coexist with rosacea. Finally, if you are not experiencing relief of your symptoms, you need to visit your dermatologist for follow up and adjustment to your current treatment.